The present disclosure relates generally to sensing systems and methods of making the same.
Since the inception of semiconductor technology, a consistent trend has been toward the development of smaller device dimensions and higher device densities. As a result, nanotechnology has seen explosive growth and generated considerable interest. Nanotechnology is centered on the fabrication and application of nano-scale structures, or structures having dimensions that are often 5 to 100 times smaller than conventional semiconductor structures. Nanowires are included in the category of nano-scale structures.
Nanowires are wire-like structures having at least one linear dimension (e.g., diameter) ranging from about 0.5 nm to about 200 nm. Nanowires are suitable for use in a variety of applications, including functioning as conventional wires for interconnection applications or as semiconductor devices. Nanowires are also the building blocks of many potential nano-scale devices, such as nano-scale field effect transistors (FETs), p-n diodes, light emitting diodes (LEDs) and nanowire-based sensors, to name a few. Nanowires have intrinsically large surface-to-volume ratios; as such, their physical properties (including electrical, mechanical and optical properties) are generally very sensitive to changes at the nanowire surfaces. This makes nanowires well suited for use as sensor devices. However, nanowire-based sensors may, in many instances, experience drawbacks, e.g., uncontrolled sensor drift, temporal fluctuations (e.g., noise), variations between devices, and chemical and/or electrical degradation and destabilization over time.